Method for detecting impurities in clopidogrel aspirin tablets

Abstract

The invention discloses a method for detecting impurities in clopidogrel aspirin tablets. Relates to the technical field of medicine. According to the detection method for the impurities in the clopidogrel aspirin tablets, the clopidogrel aspirin tablets are detected by adopting a high performance liquid chromatography, and the chromatographic conditions of the high performance liquid chromatography are as follows: a separation medium in a chromatographic column is octadecyl silica gel; the mobile phase comprises a sodium perchlorate buffer solution with the pH value of 2.0-3.0; the column temperature is less than 35 DEG C. According to the method for detecting the impurities in the clopidogrel and aspirin tablets, 13 impurities in a clopidogrel and aspirin tablet compound preparation can be detected at the same time.

Description

Technical Field

[0001] The present invention relates to the field of pharmaceutical technology, and particularly to a method for detecting impurities in clopidogrel aspirin tablets. Background Art

[0002] Acute coronary syndrome (ACS) is a group of diseases caused by the rupture or erosion of atherosclerotic plaques in the coronary arteries, leading to thrombosis, further causing complete or partial blockage of blood vessels, and thus triggering serious cardiac events. ACS includes ST-segment elevation myocardial infarction, acute non-ST-segment elevation myocardial infarction, and unstable angina. Patients often experience severe clinical symptoms due to insufficient coronary artery blood supply. If not treated promptly, it may lead to heart failure and even endanger life. To improve the prognosis of patients with acute coronary syndrome, antiplatelet therapy has become one of the cornerstones of the treatment of ACS. Especially in the routine means of secondary prevention after acute-phase treatment, antiplatelet drugs play a crucial role.

[0003] As a non-steroidal anti-inflammatory drug, aspirin can inhibit the release reaction and aggregation of platelets, and reduce the production of thromboxane A2. Thromboxane A2 is an important mediator of platelet aggregation. Aspirin exerts its antiplatelet aggregation effect by inhibiting the activity of cyclooxygenase 1 (COX-1), thereby reducing the synthesis of thromboxane A2. Clopidogrel is a drug widely used in antiplatelet therapy. It inhibits platelet activation and aggregation by selectively inhibiting the binding of adenosine diphosphate (ADP) to platelet receptors (P2Y12 receptors). As a prodrug, clopidogrel is metabolized in the liver to its active metabolite in vivo, thereby exerting its antiplatelet effect. The mechanism of clopidogrel is different from that of aspirin, and the two have complementary effects. Therefore, the combined use of aspirin and clopidogrel has significant clinical effects in the treatment of ACS.

[0004] Clopidogrel aspirin tablets are a kind of bilayer coated tablets developed by Sanofi. They have unique drug release characteristics. The pharmacokinetic curves of clopidogrel and aspirin in this compound preparation are similar to those when taken alone, and the pharmacokinetic parameters are better than those of the combined use of individual drugs, meeting the bioequivalence standard, and the efficacy is not inferior to the combined treatment with single drugs. Clopidogrel aspirin tablets simplify the treatment plan for patients. By taking 1 tablet once a day, it reduces the medication burden on patients, is convenient for long-term management, and also reduces the economic burden on patients, improving patient compliance.

[0005] However, during the research and development of compound preparations, drug degradation impurities and process impurities are quality control issues that cannot be ignored. Based on the molecular structures of clopidogrel and aspirin and relevant literature, researchers speculate that clopidogrel bisulfate will produce 6 degradation impurities in compound preparations, while aspirin has 1 degradation impurity. In addition, some process impurities may also be generated in the preparation process of the raw materials. Clopidogrel bisulfate has 2 process impurities and aspirin has 4 process impurities. These impurities may be introduced into the preparation. Therefore, at least 13 impurities may exist simultaneously in the clopidogrel aspirin tablet compound preparation. The presence of these impurities will not only affect the efficacy and safety of the drug, but also pose challenges to the quality standards and production processes of the drug.

[0006] Existing detection methods are unable to meet the demand for simultaneous detection of these impurities. For example, patent CN106324114B discloses a method for detecting specific impurities in clopidogrel bisulfate in a compound preparation. This method can only detect two specific degradation impurities and cannot meet the demand for simultaneous detection of multiple impurities. The 13 impurities described in the present invention are all recorded in the pharmacopoeia or relevant statutory standards, but existing methods cannot meet the requirements for simultaneous detection of all 13 impurities. Therefore, in order to ensure the quality of the drug, the development of an adaptable analytical method capable of simultaneous detection of 13 impurities has become an urgent problem to be solved. This poses a challenge to ensuring the quality control of the compound preparation and the safety of clinical use. Summary of the Invention

[0007] The object of the present invention is to provide a detection method capable of simultaneously detecting 13 impurities in clopidogrel aspirin tablets.

[0008] The invention provides a method for detecting impurities in clopidogrel aspirin tablets.

[0009] The present invention also proposes an application of the method for detecting impurities in clopidogrel aspirin tablets in the quality control of medicines.

[0010] A method for detecting impurities in clopidogrel aspirin tablets, comprising detecting the clopidogrel aspirin tablets using high performance liquid chromatography, wherein the chromatographic conditions of the high performance liquid chromatography include:

[0011] The separation medium in the chromatographic column was octadecyl silica gel;

[0012] The mobile phase consisted of sodium perchlorate buffer at pH 2.0–3.0;

[0013] The column temperature is less than 35°C.

[0014] According to an embodiment of the present invention, one of the technical solutions has at least one of the following advantages or beneficial effects:

[0015] There are at least 13 impurities in the clopidogrel-aspirin combination tablets. Among them, clopidogrel bisulfate will produce 6 degradation impurities in the combination preparation, while aspirin will produce 1 degradation impurity. In addition, the preparation process of the raw materials will produce some process impurities that are introduced into the preparation along with the raw materials, so that there may be 2 clopidogrel process impurities and 4 aspirin process impurities in the clopidogrel-aspirin combination tablets. The presence of these impurities will not only affect the efficacy and safety of the drugs, but also pose challenges to the quality standards and production processes of the drugs.

[0016] The method for detecting impurities in clopidogrel aspirin tablets of the present invention can simultaneously detect the above 13 impurities.

[0017] According to one embodiment of the present invention, there are 6 degradation impurities of clopidogrel bisulfate, which are referred to as impurities 1-6 in the present invention. The structural formulas of impurities 1-6 are as follows:

[0018]

[0019] Among them, impurity 2 is included in the clopidogrel bisulfate in the pharmacopoeias of various countries, and impurities 1, 3, 4, 5 and 6 are all specified in the import registration standards for clopidogrel aspirin tablets. The presence of the above impurities not only affects the efficacy and safety of the drug, but also poses challenges to the quality standards and production processes of the drug.

[0020] According to one embodiment of the present invention, the two clopidogrel process impurities are referred to as impurities 7-8 in the present invention, and their structural formulas are as follows:

[0021]

[0022] Among them, impurity 7 has been included in the relevant provisions of clopidogrel bisulfate in the pharmacopoeias of various countries, and impurity 8 has been included in the relevant provisions of clopidogrel bisulfate in the European Pharmacopoeia.

[0023] According to one embodiment of the present invention, the above-mentioned degradation impurity of aspirin is denoted as impurity 9 in the present invention, and its structural formula is as follows:

[0024] Impurity 9 has been included in the relevant regulations on aspirin in the pharmacopoeias of various countries.

[0025] According to one embodiment of the present invention, the above four aspirin process impurities are recorded as impurities 10-13 in the present invention, and their structural formulas are as follows:

[0026] Impurity 10, impurity 11, impurity 12, and impurity 13 are listed in the British Pharmacopoeia Aspirin.

[0027] According to one embodiment of the present invention, the chromatographic column is YMC-Pack ODS-AM.

[0028] According to one embodiment of the present invention, the chromatographic column is YMC-Pack ODS-AM, the inner diameter is 4.6 mm*150 mm, and the diameter of the filler particles is 3 μm.

[0029] According to one embodiment of the present invention, the mobile phase includes mobile phase A and mobile phase B, mobile phase A includes sodium perchlorate buffer with a pH of 2.0 to 3.0, and mobile phase B includes acetonitrile.

[0030] According to one embodiment of the present invention, the mobile phase A comprises a sodium perchlorate buffer solution with a pH of 2.0 to 3.0. Preferably, the mobile phase A comprises a sodium perchlorate buffer solution with a pH of 2.0 to 2.5.

[0031] According to one embodiment of the present invention, the chromatographic conditions of the high performance liquid chromatography method further include: the concentration of sodium perchlorate in mobile phase A is 30 mmol / L to 40 mmol / L. Preferably, the concentration of sodium perchlorate in mobile phase A is 35 mmol / L to 40 mmol / L.

[0032] According to one embodiment of the present invention, the volume ratio of the mobile phase A to the mobile phase B is 95-100:5-0. Preferably, the volume ratio of the mobile phase A to the mobile phase B is 95:5.

[0033] According to one embodiment of the present invention, the chromatographic conditions of the high performance liquid chromatography method further include: a column temperature of 23°C to 30°C.

[0034] According to one embodiment of the present invention, the chromatographic conditions of the high performance liquid chromatography method further include: a flow rate of 0.8 mL / min to 1.2 mL / min.

[0035] According to one embodiment of the present invention, the chromatographic conditions of the high performance liquid chromatography method further include: a detection wavelength of 220-230 nm.

[0036] According to one embodiment of the present invention, the chromatographic conditions of the high performance liquid chromatography method further include: a detection wavelength of 220 nm.

[0037] According to one embodiment of the present invention, the chromatographic conditions of the high performance liquid chromatography method further include: an elution procedure of:

[0038] Time (min) Phase A (%) Phase B (%) 0 95 5 8 95 5 15 70 30 30 65 35 40 20 80 45 20 80 45.1 95 5 50 95 5 .

[0039] According to an embodiment of the present invention, the chromatographic conditions of the high performance liquid chromatography method further include: the elution program is:

[0040]

[0041] According to an embodiment of the present invention, the chromatographic conditions of the high performance liquid chromatography method further include: the elution program is:

[0042]

[0043] Another aspect of the present invention also relates to the application of the method for detecting impurities in the clopidogrel aspirin tablets in the quality control of drugs. It includes the detection method as described in the embodiments of the first aspect above. Since this application adopts all the technical solutions of the above detection method, it has at least all the beneficial effects brought by the technical solutions of the above embodiments.

[0044] Another aspect of the present invention also relates to the application of the method for detecting impurities in the clopidogrel aspirin tablets in detecting the related substances in the clopidogrel aspirin tablets containing blank excipients. The blank excipients include at least one of microcrystalline cellulose 112, anhydrous fast-flow lactose, croscarmellose sodium, colloidal silicon dioxide, stearic acid, hypromellose, polyethylene glycol 6000, methacrylic acid / ethyl acrylate copolymer 1:1, talc powder, triethyl citrate, low-substituted hydroxypropyl cellulose, pregelatinized starch, hydrogenated castor oil, and Colorcon AMB II. The application includes the detection method as described in the embodiments of the first aspect above. Since this application adopts all the technical solutions of the above detection method, it has at least all the beneficial effects brought by the technical solutions of the above embodiments.

[0045] The additional aspects and advantages of the present invention will be partially given in the following description, partially will become obvious from the following description, or be understood through the practice of the present discovery. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The above and / or additional aspects and advantages of the present invention will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, wherein:

[0047] Figure 1 It is the chromatogram of the impurity mixed solution detected by the method of Example 1.

[0048] Figure 2 It is the chromatogram of the test sample spiked solution detected by the method of Example 1.

[0049] Figure 3 It is the chromatogram of the test sample spiked solution detected by the method of Comparative Example 1. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0050] The terms "preferred," "more preferred," and the like, used herein refer to embodiments of the present invention that may provide certain benefits under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, nor is it intended to exclude other embodiments from the scope of the present invention.

[0051] When a numerical range is disclosed herein, the range is considered continuous and includes the minimum and maximum values of the range, as well as every value between such minimum and maximum values. Further, when a range refers to an integer, every integer between the minimum and maximum values of the range is included. In addition, when multiple ranges are provided to describe a feature or characteristic, the ranges can be combined. In other words, unless otherwise indicated, all ranges disclosed herein are understood to include any and all subranges subsumed therein.

[0052] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts are within the scope of the present invention.

[0053] Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art.

[0054] In the embodiment of the present invention, the diluent is a methanol solution.

[0055] In the embodiment of the present invention, the test solution is prepared in the following manner:

[0056] Grind 20 clopidogrel / aspirin tablets, weigh approximately 740 mg of the powder, and transfer it to a 100 mL volumetric flask. Add an appropriate amount of diluent and shake for 20 minutes. Then, dilute to the mark with the diluent and shake well. Filter a portion of the solution through a 0.45 μm nylon filter. The filtrate is used as the test solution, containing 1.3 mg each of clopidogrel bisulfate and aspirin per 1 mL.

[0057] In the embodiment of the present invention, the blank auxiliary material solution is prepared in the following manner:

[0058] Weigh approximately 480 mg of blank excipients (excipients: 150 mg - 160 mg of microcrystalline cellulose 112, 130 mg - 140 mg of anhydrous fast-flow lactose, 5 mg - 10 mg of croscarmellose sodium, 2 mg - 6 mg of colloidal silicon dioxide, 1 mg - 5 mg of stearic acid, 10 mg - 15 mg of hypromellose, 35 mg - 40 mg of polyethylene glycol 6000, 25 mg - 30 mg of methacrylic acid / ethyl acrylate copolymer (1:1), 10 mg - 15 mg of talc, 1 mg - 5 mg of triethyl citrate, 30 mg - 35 mg of low-substituted hydroxypropyl cellulose, 15 mg - 20 mg of pregelatinized starch, 2 mg - 6 mg of hydrogenated castor oil, 20 mg - 30 mg of Colorcon AMB II) into a 100 mL volumetric flask, and obtain the blank excipient solution according to the preparation method of the test solution.

[0059] In the examples of the present invention, the reference solution is prepared in the following manner:

[0060] Weigh approximately 32.5 mg of clopidogrel bisulfate reference substance and approximately 25 mg of aspirin reference substance into a 25 mL volumetric flask, dissolve and dilute to the scale with the diluent, and shake well to obtain reference stock solution 1. Pipette 2 mL of reference stock solution 1 into a 100 mL volumetric flask, dilute to the scale with the diluent, and shake well to obtain reference stock solution 2. Pipette 5 mL of reference stock solution 2 into a 50 mL volumetric flask, dilute to the scale with the diluent, and shake well to obtain the reference solution.

[0061] In the examples of the present invention, the sensitivity solution is prepared in the following manner:

[0062] Precisely pipette 2 mL of the reference solution into a 20 mL volumetric flask, dilute to the scale with the diluent, and shake well to obtain the sensitivity solution.

[0063] In the examples of the present invention, the impurity localization solutions are prepared in the following manner:

[0064] Weigh 8.55 mg of impurity 1 reference substance into a 25 mL volumetric flask, 17.25 mg of impurity 2 reference substance into a 50 mL volumetric flask, 6.70 mg of impurity 3 reference substance into a 25 mL volumetric flask, 9.51 mg of impurity 4 reference substance into a 25 mL volumetric flask, 7.24 mg of impurity 5 reference substance into a 25 mL volumetric flask, 8.09 mg of impurity 6 reference substance into a 25 mL volumetric flask, 2.18 mg of impurity 7 reference substance into a 10 mL volumetric flask, 2.53 mg of impurity 8 reference substance into a 10 mL volumetric flask, 20.21 mg of impurity 9 reference substance into a 10 mL volumetric flask, 2.14 mg of impurity 10 reference substance into a 10 mL volumetric flask, 2.13 mg of impurity 11 reference substance into a 10 mL volumetric flask, 2.50 mg of impurity 12 reference substance into a 10 mL volumetric flask, 1.84 mg of impurity 13 reference substance into a 10 mL volumetric flask, dissolve with the diluent and dilute to the scale, and shake well to obtain the impurity localization solutions for each impurity.

[0065] In the embodiment of the present invention, the spiked solution of the test sample is prepared in the following manner:

[0066] Weigh 746.1 mg of clopidogrel aspirin tablet powder into a 100 mL volumetric flask, add an appropriate amount of diluent, shake for 20 min, respectively measure 1 mL of each of the localization solutions of impurity 1 to impurity 13 and add them to the volumetric flask, and make up to the scale with diluent, then shake well. Take a part of the solution and filter it through a 0.45 μm nylon filter membrane, and take the subsequent filtrate as the spiked solution of the test sample.

[0067] In the embodiment of the present invention, the mixed solution is prepared in the following manner:

[0068] Weigh 10.5 mg of clopidogrel bisulfate and 10.6 mg of aspirin into a 20 mL volumetric flask respectively, add an appropriate amount of diluent to dissolve them, respectively measure 0.5 mL of each of the localization solutions of impurity 1 to impurity 13 and add them to the volumetric flask, make up to the scale with diluent, and shake well to obtain the mixed solution.

[0069] Example 1

[0070] A method for detecting impurities in clopidogrel aspirin tablets, which uses high performance liquid chromatography to detect clopidogrel aspirin tablets. The chromatographic conditions of the high performance liquid chromatography include:

[0071] The injection volume is 10 μL;

[0072] The chromatographic column is YMC-Pack ODS-AM, with an inner diameter of 4.6 mm * 150 mm and the diameter of the packing particles is 3 μm;

[0073] The flow rate is 1 mL / min;

[0074] The column temperature is 25 °C;

[0075] The detection wavelength is 220 nm;

[0076] The mobile phase includes mobile phase A and mobile phase B. Mobile phase A is a perchlorate buffer solution with a pH of 2.5 and a volume ratio of 95:5 to acetonitrile, where the concentration of sodium perchlorate in the perchlorate buffer solution is 30 mmol / L; mobile phase B is acetonitrile;

[0077] The elution program is:

[0078] Time (min) Phase A (%) Phase B (%) 0 95 5 8 95 5 15 70 30 30 65 35 40 20 80 45 20 80 45.1 95 5 50 95 5 .

[0079] The detection results of the method of Example 1 are shown in Table 1.

[0080] Table 1

[0081]

[0082]

[0083] The method of the present invention can simultaneously detect 13 impurities in the compound preparation of clopidogrel and aspirin tablets, and neither the blank solvent nor the blank excipients interfere with the detection of the known impurities and the main component. The resolution between each known impurity and the main component is greater than 1.5, indicating that the detection method of the present invention has better specificity.

[0084] Example 2

[0085] The difference between Example 2 and Example 1 is that the column temperature in Example 2 is adjusted to 23 °C.

[0086] Example 3

[0087] The difference between Example 3 and Example 1 is that the column temperature in Example 3 is adjusted to 27 °C.

[0088] Example 4

[0089] The difference between Example 4 and Example 1 is that the column temperature in Example 4 is adjusted to 30 °C.

[0090] Example 5

[0091] The difference between Example 5 and Example 1 is that the flow rate in Example 5 is 0.8 mL / min.

[0092] Example 6

[0093] The difference between Example 6 and Example 1 is that the flow rate in Example 6 is 1.2 mL / min.

[0094] Example 7

[0095] The difference between Example 7 and Example 1 is that the pH value of mobile phase A in Example 7 is 2.0.

[0096] Example 8

[0097] The difference between Example 8 and Example 1 is that the pH value of mobile phase A in Example 8 is 3.0.

[0098] Example 9

[0099] The difference between Example 9 and Example 1 is that the concentration of sodium perchlorate in mobile phase A in Example 9 is 40 mmol / L.

[0100] Example 10

[0101] The difference between Example 10 and Example 1 is that the elution program is different.

[0102] The elution program of Example 10 is:

[0103]

[0104]

[0105] Example 11

[0106] The difference between Example 11 and Example 1 lies in the elution procedure.

[0107] The elution procedure of Example 11 is as follows:

[0108]

[0109] Comparative Example 1

[0110] A method for detecting impurities in clopidogrel aspirin tablets, which uses high performance liquid chromatography to detect clopidogrel aspirin tablets. The chromatographic conditions of the high performance liquid chromatography include:

[0111] The chromatographic column is a C18 chromatographic column;

[0112] The flow rate is 1 mL / min;

[0113] The column temperature is 35 °C;

[0114] The detection wavelength is 220 nm;

[0115] The mobile phase includes mobile phase A and mobile phase B. Mobile phase A is methanol with a volume ratio of 3:97 and sodium pentanesulfonate with a concentration of 0.05 mol / L (adjust the pH value to 2.5); mobile phase B is acetonitrile;

[0116] The elution procedure is as follows:

[0117]

[0118]

[0119] The detection results of the method of Comparative Example 1 are shown in Table 2 and Figure 3 .

[0120] Table 2

[0121]

[0122] From Table 2 and Figure 3 it can be known that the mobile phase of Comparative Example 1 uses an ion pair reagent (sodium pentanesulfonate), and its disadvantages include: 1. The chromatographic column equilibrium takes a long time; 2. The ion pair reagent is likely to combine with the chromatographic column stationary phase, causing the chromatographic column to be modified; 3. The ion pair reagent has high requirements for the stability of experimental conditions, such as small changes in pH value will affect the retention of chromatographic peaks; 4. It results in a long method running time and low efficiency.

[0123] In addition, the unreasonable column temperature, unreasonable chromatographic column, and unreasonable elution program in Comparative Example 1 all led to the inability to simultaneously detect 13 impurities in the compound preparation of clopidogrel aspirin tablets.

[0124] Comparative Example 2

[0125] The difference between Comparative Example 2 and Example 1 lies in the different chromatographic columns. The chromatographic column selected in Comparative Example 2 is Zorbax SBC8, 4.6mm * 150mm, 5μm.

[0126] Comparative Example 3

[0127] The difference between Comparative Example 3 and Example 1 lies in the different chromatographic columns. The chromatographic column selected in Comparative Example 3 is Waters XTerra RP 18, 4.6mm * 150mm, 5μm.

[0128] Comparative Example 4

[0129] The difference between Comparative Example 4 and Example 1 lies in the different mobile phase A. The mobile phase A in Comparative Example 4 is an aqueous phosphoric acid solution with a pH of 2.5 (take 1L of purified water and adjust the pH to 2.5 with phosphoric acid), acetonitrile, and the volume ratio of the aqueous phosphoric acid solution to acetonitrile is = 95:5.

[0130] Comparative Example 5

[0131] The difference between Comparative Example 5 and Example 1 lies in the different column temperatures. The column temperature in Comparative Example 5 is 20°C.

[0132] Comparative Example 6

[0133] The difference between Comparative Example 6 and Example 1 lies in the different column temperatures. The column temperature in Comparative Example 6 is 35°C.

[0134] Comparative Example 7

[0135] The difference between Comparative Example 7 and Example 1 lies in that the pH value of mobile phase A in Comparative Example 7 is 3.5.

[0136] Comparative Example 8

[0137] The difference between Comparative Example 8 and Example 1 lies in that the concentration of sodium perchlorate in mobile phase A in Comparative Example 8 is 20 mmol / L.

[0138] Comparative Example 9

[0139] The difference between Comparative Example 9 and Example 1 lies in the different elution programs.

[0140] The elution program of Comparative Example 9 is:

[0141]

[0142]

[0143] Comparative Example 10

[0144] The difference between Comparative Example 10 and Example 1 lies in the different elution procedures.

[0145] The elution procedure for Comparative Example 10 is as follows:

[0146]

[0147] Performance test:

[0148] According to the method of Example 1, 10 μL each of blank solvent, blank excipient, each impurity localization solution, mixed solution, test solution, and test solution spiked with standard were taken and injected into the liquid chromatograph, and the chromatograms were recorded. The chromatogram of the mixed solution is as shown in Figure 1 shown, and the chromatogram of the test solution spiked with standard is as shown in Figure 2 shown. It can be known from Figures 1 to 2 that the method of the present invention can simultaneously detect 13 impurities in the compound preparation of clopidogrel and aspirin tablets, and the blank solvent and blank excipient have no interference on the main peak and each impurity, and complete separation can be achieved between all impurities and the main peak, with a resolution greater than 1.5.

[0149] According to the methods of Comparative Examples 2 - 3, 10 μL of the mixed solution was accurately measured and injected into the high - performance liquid chromatograph, and the detection results are shown in Table 3.

[0150] Table 3

[0151]

[0152]

[0153] According to the method of Comparative Example 4, 10 μL of the mixed solution was accurately measured and injected into the high - performance liquid chromatograph, and the detection results are shown in Table 4.

[0154] Table 4

[0155]

[0156]

[0157] According to the methods of Examples 2 - 4 and Comparative Examples 5 - 6, 10 μL of the mixed solution was accurately measured and injected into the high - performance liquid chromatograph, and the detection results are shown in Table 5.

[0158] Table 5

[0159]

[0160] According to the methods of Examples 5 - 6, 10 μL of the mixed solution was accurately measured and injected into the high - performance liquid chromatograph, and the detection results are shown in Table 6.

[0161] Table 6

[0162]

[0163]

[0164] Precisely measure 10 μL of the mixed solution according to the methods of Examples 7 - 8 and Comparative Example 7, inject it into a high - performance liquid chromatograph, and the detection results are shown in Table 7.

[0165] Table 7

[0166]

[0167] Precisely measure 10 μL of the mixed solution according to the methods of Example 9 and Comparative Example 8, inject it into a high - performance liquid chromatograph, and the detection results are shown in Table 8.

[0168] Table 8

[0169]

[0170]

[0171] Precisely measure 10 μL of the mixed solution according to the methods of Examples 10 - 11 and Comparative Examples 9 - 10, inject it into a high - performance liquid chromatograph, and the detection results are shown in Table 9.

[0172] Table 9

[0173]

[0174] The injection precision of the method of the present invention was investigated. The test sample spiked solution was continuously injected 6 times according to the method of Example 1 of the present invention, and the injection precision results of 13 impurities are shown in Table 10 below.

[0175] Table 10

[0176]

[0177] It can be seen from Table 10 that the RSD of the peak areas of each impurity is less than 2.0%, indicating that the detection and analysis method of the present invention has good repeatability.

[0178] The detection limit and quantification limit of the method of the present invention were investigated. Appropriate amounts of impurities 1 - 13, aspirin, and clopidogrel bisulfate reference substances were taken, dissolved separately with a diluent (methanol) and gradually diluted. Combining the impurity reporting limits and signal - to - noise ratio requirements in ICH (detection limit signal - to - noise ratio ≥ 3:1, quantification limit signal - to - noise ratio ≥ 10:1), the detection limit and quantification limit results of this analysis method are shown in Table 11.

[0179] Table 11

[0180]

[0181]

[0182] It can be seen from Table 11 that the detection limit concentration of each of the above impurities is no more than 0.019% of the test solution concentration, and the quantitative limit concentration is no more than 0.038% of the test solution concentration. The sensitivity meets the requirements for preparation impurity analysis.

[0183] The linear regression of the method of the present invention was investigated. Appropriate amounts of impurities 1 to 13, aspirin, and clopidogrel bisulfate reference substances were dissolved and diluted with a diluent (methanol) to prepare a series of mixed solutions with gradient concentrations. 10 μL was accurately measured and injected into a liquid chromatograph. The standard curves of each component were drawn with the peak area as the ordinate and the corresponding concentration C as the abscissa. The linear regression equation was calculated. The results are shown in Table 12.

[0184] Table 12

[0185] Name Linear range Linear equation <![CDATA[R 2 > Impurity 1 0.1142 - 4.5892 μg / mL y = 67.416X + 4.757 0.998 Impurity 2 0.1725 - 6.9000 μg / mL y = 23.329X + 4.202 0.994 Impurity 3 0.2140 - 4.2794 μg / mL y = 30.617X + 2.346 0.995 Impurity 4 0.3427 - 6.8548 μg / mL y = 25.251X + 4.581 0.998 Impurity 5 0.2699 - 5.3981 μg / mL y = 26.869X + 8.624 0.996 Impurity 6 0.3171 - 6.3426 μg / mL y = 24.640X + 7.100 0.992 Impurity 7 0.4360 - 4.3600 μg / mL y = 18.288X + 2.645 0.999 Impurity 8 0.4973 - 4.9735 μg / mL y = 20.668X + 0.010 1.000 Impurity 9 0.4038 - 40.3798 μg / mL y = 20.127X + 4.897 1.000 Impurity 10 0.4266 - 4.2663 μg / mL y = 20.744X + 0.361 0.999 Impurity 11 0.2111 - 4.2218 μg / mL y = 96.108X + 1.512 1.000 Impurity 12 0.4903 - 4.9030 μg / mL y = 25.146X + 0.369 1.000 Impurity 13 0.3566 - 3.5659 μg / mL y = 28.499X + 0.554 1.000 Aspirin 0.2162 - 4.3240 μg / mL y = 19.941X + 0.097 0.999 Clopidogrel bisulfate 0.1972 - 3.9441 μg / mL y = 16.439X + 1.054 1.000 .

[0186] As shown in Table 12, impurities 1 to 13, aspirin, and clopidogrel bisulfate have good linearity, indicating that the method of the present invention has good linearity and is beneficial for detecting impurities in clopidogrel aspirin tablets.

[0187] The above are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention specification, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for detecting impurities in clopidogrel aspirin tablets, characterized in that, The clopidogrel aspirin tablets are detected by high performance liquid chromatography. The chromatographic conditions of the high performance liquid chromatography include: The separation medium in the chromatographic column is octadecyl silica gel; The mobile phase includes sodium perchlorate buffer solution with pH 2.0 - 3.0; The column temperature is less than 35 °C.

2. The detection method according to claim 1, wherein The chromatographic column is YMC - Pack ODS-AM.

3. The detection method according to claim 1, wherein, The mobile phase includes mobile phase A and mobile phase B. Mobile phase A includes sodium perchlorate buffer solution with pH 2.0 - 3.0, and mobile phase B includes acetonitrile.

4. A detection method according to claim 3, characterized in that The chromatographic conditions of the high performance liquid chromatography further include: the concentration of sodium perchlorate in mobile phase A is 30 mmol / L - 40 mmol / L.

5. The detection method according to claim 3, characterized in that, The volume ratio of mobile phase A to mobile phase B is 95 - 100:5 - 0.

6. The detection method according to claim 1, characterized in that, The chromatographic conditions of the high performance liquid chromatography further include: the flow rate is 0.8 mL / min - 1.2 mL / min.

7. The detection method according to claim 1, characterized in that, The chromatographic conditions of the high performance liquid chromatography further include: the elution program is:

8. The detection method according to claim 1, wherein The chromatographic conditions of the high performance liquid chromatography further include: the elution program is:

9. The detection method according to claim 1, wherein, The chromatographic conditions of the high performance liquid chromatography further include: the elution program is:

10. Use of the detection method according to claim 1 for detecting related substances in clopidogrel aspirin tablets containing blank excipients, wherein the blank excipients include at least one of microcrystalline cellulose 112, anhydrous fast-flow lactose, croscarmellose sodium, colloidal silicon dioxide, stearic acid, hypromellose, polyethylene glycol 6000, methyl methacrylate / ethyl acrylate copolymer 1:1, talc, triethyl citrate, low-substituted hydroxypropyl cellulose, pregelatinized starch, hydrogenated castor oil, and Colorcon AMB II.

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